Document metadata

6 files changed, 78 insertions, 45 deletions

diff --git a/library/src/layout/mod.rs b/library/src/layout/mod.rs
index 100e0611..e63a072e 100644
--- a/library/src/layout/mod.rs
+++ b/library/src/layout/mod.rs
@@ -29,7 +29,7 @@ use std::mem;
 use comemo::Tracked;
 use typed_arena::Arena;
 use typst::diag::SourceResult;
-use typst::frame::Frame;
+use typst::doc::Frame;
 use typst::geom::*;
 use typst::model::{
     applicable, capability, realize, Content, Node, SequenceNode, Style, StyleChain,
@@ -40,7 +40,7 @@ use typst::World;
 use crate::prelude::*;
 use crate::shared::BehavedBuilder;
 use crate::structure::{
-    DescNode, DocNode, EnumNode, ListItem, ListNode, DESC, ENUM, LIST,
+    DescNode, DocumentNode, EnumNode, ListItem, ListNode, DESC, ENUM, LIST,
 };
 use crate::text::{
     LinebreakNode, ParNode, ParbreakNode, SmartQuoteNode, SpaceNode, TextNode,
@@ -54,7 +54,7 @@ pub trait LayoutRoot {
         &self,
         world: Tracked<dyn World>,
         styles: StyleChain,
-    ) -> SourceResult<Vec<Frame>>;
+    ) -> SourceResult<Document>;
 }
 
 impl LayoutRoot for Content {
@@ -63,7 +63,7 @@ impl LayoutRoot for Content {
         &self,
         world: Tracked<dyn World>,
         styles: StyleChain,
-    ) -> SourceResult<Vec<Frame>> {
+    ) -> SourceResult<Document> {
         let scratch = Scratch::default();
         let (realized, styles) = realize_root(world, &scratch, self, styles)?;
         realized.with::<dyn LayoutRoot>().unwrap().layout_root(world, styles)
@@ -245,7 +245,7 @@ fn realize_root<'a>(
     builder.accept(content, styles)?;
     builder.interrupt_page(Some(styles))?;
     let (pages, shared) = builder.doc.unwrap().pages.finish();
-    Ok((DocNode(pages).pack(), shared))
+    Ok((DocumentNode(pages).pack(), shared))
 }
 
 /// Realize into a node that is capable of block-level layout.
@@ -357,6 +357,10 @@ impl<'a> Builder<'a> {
             }
         }
 
+        if let Some(span) = content.span() {
+            bail!(span, "not allowed here");
+        }
+
         Ok(())
     }
 
@@ -378,13 +382,26 @@ impl<'a> Builder<'a> {
         map: &StyleMap,
         styles: Option<StyleChain<'a>>,
     ) -> SourceResult<()> {
-        if map.interrupts::<PageNode>() {
+        if let Some(Some(span)) = map.interruption::<DocumentNode>() {
+            if self.doc.is_none() {
+                bail!(span, "not allowed here");
+            }
+            if !self.flow.0.is_empty()
+                || !self.par.0.is_empty()
+                || !self.list.items.is_empty()
+            {
+                bail!(span, "must appear before any content");
+            }
+        } else if let Some(Some(span)) = map.interruption::<PageNode>() {
+            if self.doc.is_none() {
+                bail!(span, "not allowed here");
+            }
             self.interrupt_page(styles)?;
-        } else if map.interrupts::<ParNode>() {
+        } else if map.interruption::<ParNode>().is_some() {
             self.interrupt_par()?;
-        } else if map.interrupts::<ListNode>()
-            || map.interrupts::<EnumNode>()
-            || map.interrupts::<DescNode>()
+        } else if map.interruption::<ListNode>().is_some()
+            || map.interruption::<EnumNode>().is_some()
+            || map.interruption::<DescNode>().is_some()
         {
             self.interrupt_list()?;
         }
diff --git a/library/src/lib.rs b/library/src/lib.rs
index 6107cf42..cf8cb490 100644
--- a/library/src/lib.rs
+++ b/library/src/lib.rs
@@ -44,6 +44,7 @@ fn scope() -> Scope {
     std.def_fn("smallcaps", text::smallcaps);
 
     // Structure.
+    std.def_node::<structure::DocumentNode>("document");
     std.def_node::<structure::RefNode>("ref");
     std.def_node::<structure::HeadingNode>("heading");
     std.def_node::<structure::ListNode>("list");
diff --git a/library/src/prelude.rs b/library/src/prelude.rs
index 6379e579..bc0ec31d 100644
--- a/library/src/prelude.rs
+++ b/library/src/prelude.rs
@@ -10,7 +10,7 @@ pub use comemo::Tracked;
 #[doc(no_inline)]
 pub use typst::diag::{bail, error, with_alternative, At, SourceResult, StrResult};
 #[doc(no_inline)]
-pub use typst::frame::*;
+pub use typst::doc::*;
 #[doc(no_inline)]
 pub use typst::geom::*;
 #[doc(no_inline)]
diff --git a/library/src/structure/doc.rs b/library/src/structure/doc.rs
deleted file mode 100644
index e471a852..00000000
--- a/library/src/structure/doc.rs
+++ /dev/null
@@ -1,32 +0,0 @@
-use crate::layout::{LayoutRoot, PageNode};
-use crate::prelude::*;
-
-/// A sequence of page runs.
-#[derive(Hash)]
-pub struct DocNode(pub StyleVec<PageNode>);
-
-#[node(LayoutRoot)]
-impl DocNode {}
-
-impl LayoutRoot for DocNode {
-    /// Layout the document into a sequence of frames, one per page.
-    fn layout_root(
-        &self,
-        world: Tracked<dyn World>,
-        styles: StyleChain,
-    ) -> SourceResult<Vec<Frame>> {
-        let mut frames = vec![];
-        for (page, map) in self.0.iter() {
-            let number = 1 + frames.len();
-            frames.extend(page.layout(world, number, styles.chain(map))?);
-        }
-        Ok(frames)
-    }
-}
-
-impl Debug for DocNode {
-    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
-        f.write_str("Doc ")?;
-        self.0.fmt(f)
-    }
-}
diff --git a/library/src/structure/document.rs b/library/src/structure/document.rs
new file mode 100644
index 00000000..2e5761e0
--- /dev/null
+++ b/library/src/structure/document.rs
@@ -0,0 +1,47 @@
+use crate::layout::{LayoutRoot, PageNode};
+use crate::prelude::*;
+
+/// The root node of the model.
+#[derive(Hash)]
+pub struct DocumentNode(pub StyleVec<PageNode>);
+
+#[node(LayoutRoot)]
+impl DocumentNode {
+    /// The document's title.
+    #[property(referenced)]
+    pub const TITLE: Option<EcoString> = None;
+
+    /// The document's author.
+    #[property(referenced)]
+    pub const AUTHOR: Option<EcoString> = None;
+}
+
+impl LayoutRoot for DocumentNode {
+    /// Layout the document into a sequence of frames, one per page.
+    fn layout_root(
+        &self,
+        world: Tracked<dyn World>,
+        styles: StyleChain,
+    ) -> SourceResult<Document> {
+        let mut pages = vec![];
+        for (page, map) in self.0.iter() {
+            let number = 1 + pages.len();
+            pages.extend(page.layout(world, number, styles.chain(map))?);
+        }
+
+        Ok(Document {
+            metadata: Metadata {
+                title: styles.get(Self::TITLE).clone(),
+                author: styles.get(Self::AUTHOR).clone(),
+            },
+            pages,
+        })
+    }
+}
+
+impl Debug for DocumentNode {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        f.write_str("Document ")?;
+        self.0.fmt(f)
+    }
+}
diff --git a/library/src/structure/mod.rs b/library/src/structure/mod.rs
index 8e13f76a..a1c27eed 100644
--- a/library/src/structure/mod.rs
+++ b/library/src/structure/mod.rs
@@ -1,12 +1,12 @@
 //! Document structuring.
 
-mod doc;
+mod document;
 mod heading;
 mod list;
 mod reference;
 mod table;
 
-pub use self::doc::*;
+pub use self::document::*;
 pub use self::heading::*;
 pub use self::list::*;
 pub use self::reference::*;